Stagger blanking mechanism



3 Sheets-Sheet 1 Filed Oct. 17, 1963 INVENTOR EM Ma Degw ATTORNEYS Oct.26, 1965 E. B. BYAM 3,213,730

STAGGER BLANKING MECHANISM Filed Oct. 17, 1963 3 Sheets-Sheet 2 INVENTOREMMA) De w ATTORNEYS Oct. 26, 1965 E. B. BYAM 3,213,730

STAGGER BLANKING MECHANISM Filed Oct. 17, 1965 3 Sheets-Sheet 3 INVENTORKM M pe w ATTORNEYS United States Patent ice 3,213,730 STAGGER BLANKTNGMEQHANISM Erwin B. Byam, Welcott, Conn, assignor to Textron Inc.,Providence, 12.1., a corporation of Rhode Island Filed Oct. 17, 1963,Ser. No. 317,014 8 Claims. (Cl. 83-166) This invention relates generallyto a blanking mechanism and, more particularly, to a blanking mechanismforming an integral part of a press for blanking workpieces from a stripof material while providing maximum utilization of the material.

Blanking, as it is known in the art, is the piercing of a workpiece fromthe material stock usually continuously supplied to the blankingmechanism. The blanked workpieces are then transferred to haveadditional operations performed on them. The size and shape of theworkpiece to be blanked is dependent upon the article into which it willbe formed. Very often, the workpiece is blanked in the form of a round,flat disc blanked from a wide strip of fiat material. From considerationof geometrical factors, it will be seen that, if a round disc is blankedfrom a continuous strip of metal with the discs being in alignment alongthe strip, substantial stock will remain on the strip. Since the stripwith the workpieces blanked therefrom is reduced to scrap, it is quiteclear that considerable waste is involved.

In order to reduce waste, it is known to stagger the blanked discs on awider strip, thereby reducing the amount of scrap per disc. This can beaccomplished in a number of ways. Firstly, the blanking die could beprovided with two die cavities and two punches so that two staggereddiscs are concurrently blanked from the strip. However, the additionalcost for the second punch and die makes this procedure economicallyundesirable. A second alternative would be to shift the strip laterallybetween consecutive blanking operations to stagger the discs or blanks.The major shortcomings of this system are the problems created inshifting a bulky roll of strip material. The third solution would be tolaterally shift the punch and die on consecutive blanking operations soas to stagger the blanks without the necessity of shifting the roll ofstrip. This last-mentioned system has proven to be the most desirable.

Accordingly, it is an object of this invention to provide an improvedmechanism for staggering workpieces blanked from continuous strip.

Another object of this invention is to provide an improved staggerblanking mechanism integral with a press which performs subsequentoperations on the blanked workpieces.

A further object of the invention is to provide an improved staggerblanking mechanism integral with a press having simplified means fortransferring the blanked workpieces to the next operating station of thepress.

A still further object of the invention is to provide improved means forlaterally shifting a punch and die on consecutive strokes of a press forstaggering the workpieces blanked from a strip of material.

Still other objects and advantages of the invention will in part beobvious and will in part be apparent from the specification.

Generally speaking, in accordance with the invention, a press such as amulti-plunger press carries a punch and die shitfable along a lineparallel to the line of transfer between consecutive stations of thepress. Additionally, the punch is adapted to be reciprocated toward andfrom the die by means of one of the plungers of the multiplunger press.The punch and die are shifted through a plurality of linkages driven intimed relation with the reciprocation of the punch with the linkagesbeing inter- 3,213,730 Patented Oct. 26, 1965.

connected in such a manner that the location and stroke of the shiftingpunch and die set may readily be adjusted. In synchronism with theblanking operation, yieldable means operate to transfer a blankedworkpiece to the next operating station. The yieldable means minimizethe possibility of damage to the machine in the event that one of theworkpieces being transferred becomes jammed in the mechanism.

The invention accordingly comprises the features of construction,combination of elements and arrangement of parts which will beexemplified in the construction hereinafter set forth, and the scope ofthe invention will be indicated in the claims.

For a fuller understanding of the invention, reference is had to thefollowing description taken in connection with the accompanyingdrawings, in which:

FIG. 1 is a partial side elevational view of a machine constructed inaccordance with the invention;

FIG. 2 is a partial front elevational view, partly in section, of amachine constructed in accordance with the invention;

FIG. 3 is a partial sectional view taken along line 33 of FIG. 2;

FIG. 4 is a partial sectional View taken along line 44 of FIG. 2; and

FIG. 5 is a partial sectional view taken along line 5-5 of FIG. 1.

Before commencing with a detailed description of the drawings, it shouldbe noted that the mechanism embodying the invention herein is shown asbeing incorporated in a multi-plunger press wherein each of the plungersare separately actuated from a single driveshaft. As is known in theart, the plungers may be operated through cams or pitmans and the modeof operation of the plungers does not in any way affect the instantinvention. Furthermore, the instant invention is equally adaptable foruse in headers and like mechanisms wherein all the punches are normallymounted to and operated by a single gate. Thus, the disclosure of themechanism forming the invention herein in conjunction with amultiplunger press, is not to be considered as a limitation here-Referring now to FIGS. 1 and 2, journalled in the machine frame 11 is adriveshaft 12 drivingly connected to a shaft 13 through bevelled gears14. Shaft 13 is also journalled for rotation in the machine frame. Themachine frame carries a die bed 15 on which is slidably mounted acarrier 16 formed of a lower half 17 and an upper half 18. The lowerhalf of the carrier is slidably mounted to die bed 15 and carries a die19. Lower half 17 slidably engages a pair of guides 21 (FIG. 3) whichguide it for sliding movement toward the left and right as viewed inFIGS. 2 and 3. Upper half 18 is rigidly secured to lower half 17 formovement therewith. Upper half 18 is provided with a wide arm portion 22which is also guided for sliding movement in the machine frame by meansof a pair of guides 23 also secured to the frame. Upper half 18 carriesa bearing 24 which slidably receives a punch 25. Punch 25 is adapted tocooperate with die 19 for blanking a workpiece on reciprocation of thepunch. Since both the punch and die are carried by carrier 16, theirrelative positions will be unaffected by the sliding movement of thecarrier in the machine frame.

A plunger 26 of the multi-plunger press is positioned above punch 25 andis adapted to reciprocate the punch in the direction shown by the arrowin FIG. 2. The plunger, of course, does not move laterally with theshiftable carrier and means are therefore provided to permit relativelateral movement between punch 25 and the plunger while securing thepunch to the plunger for the purpose of reciprocating the punch.Referring especially to FIGS. 2 and 4, plunger 26, which is slidablymounted in machine frame 11, is provided, in its lower face thereof,with a wide elongated slot 27 and a narrow elongated slot 28. A pair ofblocks 29 are secured in the wide elongated slot and form a dovetailgroove which cooperates with a dovetail tongue 30 on the uppermostportion of unch 25. Through the dovetail arrangement, the punch is freeto move laterally with respect to the plunger 'but is secured to theplunger for up and down movement. A pin 31 is slidably mounted withinthe punch along the central axis thereof and is urged outwardly ortoward die 19 by means of a spring 32. The use of which pin will behereafter described.

Referring again to FIGS. 1 through 3, a bell crank 33 is pivoted to themachine frame intermediate its ends and a link 34 is pivotably connectedbetween one end of the bell crank and arm portion 22. It willimmediately be seen that rocking or arcuate movement of ball crank 33will effect reciprocation of carrier 16 through link 34. A block 35 ispivoted to the other end of hell crank 33 and threadedly receives oneend of an adjusting bolt 36. The other end of the adjusting bolt isthreadedly received in a block 37 which is adjustably connected to anarm 38. The position of block 37 along the longitudinal axis of arm 38may be adjusted by means of a bolt 39.

Arm 38 is secured at its innner end fast on a shaft 41 which isrotatably journalled in the machine frame. Also mounted fast on shaft41, spaced from arm 38, is a bifurcated bell crank 42 having a first arm43 and a second arm 44. First arm 43 carries a cam follower 45 engagingthe surface of a cam 46 which is mounted on and rotates with shaft 13.Second arm 44 carries a cam follower 47 which engages and rides on thesurface of a cam 48 also mounted fast on shaft 13 for rotationtherewith. The cam followers 45 and 47 are disposed on opposite sides ofcams 46 and 48 with respect to the center of the cam pivots. In thismanner, cam 46 positively rotates bell crank 42 .in a clockwisedirection (as seen in FIG. 3) on shaft 41 while cam 48 positivelyrotates bell crank 42 in a counterclockwise direction. Through arm 38and bell crank 33, positive reciprocation of carrier 16 is provided for.

With any preselected profile of cams 46 and 48, control may be had overboth the stroke of carrier 16 and the position of the carrier at itsshifted positions. The position of the carrier is controlled by suitableadjustment of adjusting bolt 36 wherein the lengthening of distancebetween blocks 35 and 37 will position the carrier more toward the rightas viewed in FIG. 3 and the shortening of the distance between theblocks will move the carrier more toward the left. By suitableadjustment of bolt 39, block 37 may be moved closer or further from thecenter of shaft 41. By increasing the distance, the length of the arethrough which block 37 is moved on any particular degree of arcuatetravel of arm 38 is increased, thereby increasing the stroke or thedistance of shifting of carrier 16. Reverse adjustment converselydecreases the stroke.

The material from which the workpieces or discs are blanked is usuallysupplied to the blanking station from a large roll mounted adjacent thefront of the machine with a take-up reel being provided adjacent therear of the machine. The strip, indicated at 49, is fed past theblanking station in the direction indicated by the arrow in FIG. 3 andis guided between rolls 51. Since the means for feeding the strip formno part of the invention herein, no description thereof is deemednecessary. It must, however, be noted that the strip is fedintermittently so that the strip is not moving at the time during whichthe disc is being blanked from the strip.

The strip passes between the punch and die and a disc is blanked fromthe strip on each reciprocation of plunger 26. As seen in FIG. 3, therate of strip feed is synchronized with the reciprocation of the plungerand the shifting of the punch and die to provide maximum utilization ofthe strip material, thereby minimizing waste. Plunger 26 is reciprocatedby means (not shown) which also drive 4 shafts 12 and 13. The profile ofcams 46 and 48 and the speed of shaft 13 is so selected that the punchand die is shifted after each reciprocation of the plunger.

Referring more specifically to FIGS. 1, 2 and 5, strip 49 is fed intothe blanking station along the surface of die 19. Upon reciprocation ofplunger 26, punch 25 blanks a disc 52 from the strip and carries itthrough the die to the surface of die bed 15. This is clearly shown inFIG. 2. As the plunger and punch recede, pin 31 extends beyond thesurface of the punch under the force of spring 32 to assure that thedisc does not adhere to the face of the punch. A pusher blade 53 isslidably mounted along the face of die bed 15 and is adapted to beadvanced to the left as shown in FIG. 2 to clear the blanked disc 52 tothe next operating station of the machine where forming operations willthen be performed. Thereafter, the usual transfer mechanisms in machinesof this general type will carry the workpiece between subsequentstations. The mechanism for operating pusher blade 53 will now bedescribed.

A slide 54 is slidably dovetailed in the machine frame as shown in FIG.1 and pusher blade 53 is secured thereto. An arm 55 is secured to slide54 and one end of a link 56 is pivoted to arm 55. The other end of link56 is mounted fast on a shaft 57 rotatably mounted in the machine frame.One end of second link 58 is also mounted fast on shaft 57 for rotationtherewith and the other end of link 58 carries a cam follower 59. Camfollower 59 engages the surface of a cam 61 which is secured to shaft13. A pair of springs 62 act between arm 55 and the machine frame,urging slide 54 to the left as shown in FIG. 2. Springs 62 yieldablyurge shaft 57 in a counterclockwise direction thereby holding camfollower 59 against the surface of cam 61.

After a disc has been blanked from the stock and punch 25 commences torecede, the rotation of shaft 13 brings the low side of cam 61 below camfollower 59, thereby permitting link 58 to rotate in a counterclockwisedirection under the tension of springs 62. The counterclockwisemovement, through link 56, moves slide 54 and pusher blade 53 to theleft (FIG. 2) and clears disc 52 to the next operating station. Afterthe disc is cleared, cam follower 59 will approach the high side of cam61 thereby causing clockwise rotation of shaft 57 and withdrawing thepusher blade to the right to move it to a non-interfering position. Itwill also be noted that, at the same time, the punch and die will beshifted to its alternate position prior to advance of the plunger forthe next blanking operation. The clearing movement of pusher blade 53takes place by means of the tension of springs 62 rather than under thepositive drive of cam 61. By this means, damage to the pusher blade willbe avoided if the disc should become jammed.

In some blanking operations, such as where the disc to be blanked has adiameter approaching the width of the strip, it may be desirable torender the punch and die shifting mechanism inoperative and lock it in acentral position. In such case, a boss 63 (FIG. 2) is provided on themachine frame. Arm portion 22 is disconnected from link 34 and a pin issecured through the pivot of arm portion 22 into a suitable aperture 64in boss 63. Link 34 will also be disconnected from bell crank 33 so longas carrier 16 and the punch and die are to be held stationary. Note thatduring the stationary operation, bell crank 33 Will continue to beoperated through cams 46 and 48 but the operation will be ineffective.However, during the stationary operation, the operation of pusher blade53 is in no Way affected and the pusher blade will continue to clear theblanked discs to the next machine station.

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are efficiently attained and,since certain changes may be made in the above construction withoutdeparting from the spirit and scope of the invention, it is intendedthat all matter contained in the above description or shown in theaccompanying drawings shall be interpreted as illustrative and not in alimiting sense.

It is also to be understood that the following claims are intended tocover all of the generic and specific features of the invention hereindescribed, and all statements of the scope of the invention which, as amatter of language, might be said to fall therebetween.

What is claimed is:

1. In a machine of the class described having a frame, a die bed, amember reciprocated toward and from the die bed, and drive means forreciprocating said member, the combination comprising a carrier slidablymounted on the die bed, a die mounted in said carrier, a punch slidablymounted in said carrier, means slidably mounting said punch to thereciprocated member, and means driven by the driven means for slidablyshifting said carrier in timed relation to the reciprocation of themember.

2. The structure defined in claim 1 wherein said lastnamed meanscomprises a cam driven through the drive means, a crank pivoted to themachine frame and cooperatively engaging said cam, and a link connectedbetween said carrier and said crank for reciprocating said carrier inresponse to the rocking movement of said crank.

3. The structure defined in claim 1 wherein said lastnamed meanscomprises a pair of cams driven through said drive means, a crankpivoted to the machine frame and provided with follower portionsengaging the surface of each cam, a second crank pivoted to the machineframe, adjustable means interconnecting said first and second cranks,and a link acting between said second crank and said carrier.

4. The structure defined in claim 3 wherein said adjustable meanscomprises a first link pivoted at one end to said second crank, anadjustable threaded member threadedly engaging the other end of saidfirst link, a second link threadedly receiving the other end of saidthreaded member, said second link being connected to said first crank,and means for adjusting said second link toward and from the pivot ofsaid first crank.

5. In a machine of the class described having a frame, a die bed, amember reciprocated toward and from the die bed, and drive means forreciprocating said member, the combination comprising a carrier slidablymounted on the die bed, a die mounted in said carrier, a punch slidablymounted in said carrier, means slidably mounting said punch to thereciprocated member, and camoperated means driven by the drive means forslidably shifting said carrier in timed relation to the reciprocation ofthe member.

6. In a machine of the class described having a frame, a die bed, amember reciprocated toward and from the die bed, and drive means forreciprocating said member, the combination comprising a carrier slidablymounted on the die bed and having at least a portion thereof spaced fromsaid die bed, a die mounted in said carrier in spaced relation with saiddie bed, a punch slidably mounted in said carrier, means slidablymounting said punchto the reciprocated member, means driven by the drivemeans for slidably shifting said carrier in timed relation to thereciprocation of the member, and pusher means slidably positionedbetween said die bed and said carrier and reciprocated toward and fromsaid die after each advancement of said puch within said die.

7. The structure defined in claim 6 wherein said pusher means comprisesa blade slidably mounted on said die bed, a blade carrier slidablymounted in the machine frame for movement along a single axis, saidblade being attached to said blade carrier, a crank pivoted intermediateits ends to the machine frame, said crank being pivoted at one end tosaid blade carrier, a cam driven by the drive means, said camcooperatively engaging the other end of said crank, and spring-biasedmeans acting between the machine frame and the blade carrier for urgingsaid blade carrier toward said die.

8. In a machine of the class described having a frame, a die bed, amember reciprocated toward and from the die bed, and drive means forreciprocating said member, the combination comprising a carrier slidablymounted on the die bed, a die mounted in said carrier, a punch slidablymounted in said carrier, means slidably mounting said punch to thereciprocated member, a shaft journalled in the machine frame and driventhrough the drive means, a plurality of cams mounted fast on said shaft,a crank assembly acting between at least one of said cams and saidcarrier for shifting said carrier in timed relation to the reciprocationof the member, a pusher blade slidably mounted in the machine frame foradvancement between said die and the die bed, springbiased means urgingsaid pusher blade toward said die, and a crank operated by another ofsaid cams for withdrawing said pusher blade from the position proximateto the die.

No references cited.

ANDREW R. JUHASZ, Primary Examiner.

6. IN A MACHINE OF THE CLASS DESCRIBED HAVING A FRAME, A DIE BED, A MEMBER RECIPROCATED TOWARD AND FROM THE DIE BED, AND DRIVE MEANS FOR RECIPROCATING SAID MEMBER, THE COMBINATION COMPRISING A CARRIER SLIDABLY MOUNTED ON THE DIE BED AND HAVING AT LEAST A PORTION THEREOF SPACED FROM SAID DIE BED, A DIE MOUNTED IN SAID CARRIER IN SPACED RELATION WITH SAID DIE BED, A PUNCH SLIDABLY MOUNTED IN SAID CARRIER, MEANS SLIDABLY MOUNTING SAID PUNCH TO THE RECIPROCATED MEMBER, MEANS DRIVEN BY THE DRIVE MEANS FOR SLIDABLY SHIFTING SAID CARRIER IN TIMED RELATION TO THE RECIPROCATION OF THE MEMBER, AND PUSHER MEANS SLIDABLY POSITIONED BETWEEN SAID DIE BED AND SAID 